The present application relates to lighting and illumination devices and systems.
It is well known that conventional light sources also emit heat that may be undesirable. For example, it has been known for over a century that incandescent light bulbs may waste energy by generating a substantial amount of heat as well as light. On the other hand, it has been known for many decades that light emitting diodes (LEDs) may waste less energy in producing light, but are less efficient and can have reduced lifetimes when operated at elevated temperatures produced by the LEDs. Moreover, LED lighting devices have a much higher upfront cost than incandescent light bulbs, although the cost may be recouped over time if the LED lifetime is sufficient. Thus, there is a longstanding need for a lighting device that is more efficient and long-lived, yet cost-efficient.